This survey focused on two species of common dolphin: the short-beaked common dolphin, Delphinus delphis, and the long-beaked common dolphin, Delphinus capensis, off southern California, USA and Baja California, Mexico. Our goal was to answer the following questions:

Both species of common dolphin inhabit the waters of the Southern CA Bight, an area that stretches from Point Conception to south of San Diego and includes the Channel Islands. This area is a major part of our study area, which includes the large coastal urban centers of Los Angeles and San Diego. The dolphins in this area are at risk from commercial and recreational fishing activities (for example, dolphins are caught as bycatch [a copy of the Pacific Marine Mammal Stock Assessment Report is available in pdf format]), and pollution generated by activities on land and in the ocean. Finding answers to the above questions during this study will enable us to make sound management decisions about these protected species.